Question: Solve for $x$ : $2\sqrt{x} - 4 = 5\sqrt{x} + 5$
Subtract $2\sqrt{x}$ from both sides: $(2\sqrt{x} - 4) - 2\sqrt{x} = (5\sqrt{x} + 5) - 2\sqrt{x}$ $-4 = 3\sqrt{x} + 5$ Subtract $5$ from both sides: $-4 - 5 = (3\sqrt{x} + 5) - 5$ $-9 = 3\sqrt{x}$ Divide both sides by $3$ $\frac{-9}{3} = \frac{3\sqrt{x}}{3}$ Simplify. $-3 = \sqrt{x}$ The principal root of a number cannot be negative. So, there is no solution.